[FOREIGN]. Okay, the first one is the textbook. I used this one, the Neuroscience by Mark Bear. This one I can see is quite easy to understand. It's quite simple. But we also use another one. This one is the Principles of Neural Science. Maybe, [LAUGH] you guys already have this textbook, right? Everybody have this one, a copy of the electronic one? Okay, good. So this one, then, is actually quite comprehensive. A lot of stuff inside. And then you need to spend a lot of time to digest those content. And actually, there was another really good textbook, Principles of Neurobiology, Liqun Luo. Everybody knows. These three books actually I use kind of often when I prepare for these lectures. Okay, this is the first one, actually I talk about it the textbook you can read before my lectures or in the future for your exam, I don't know whether you have examination or not. Okay the second one I want to talk about actually this PPT, I will not release to any of you. So that means, you need really participate in the lectures and study really hard, and if you don't understand anything here, then just usually ask questions, okay. I will explain to you. So that is two points I wanted to talk about. I guess, and, Dr John already talked about this on basics on neuroscience. For example, you know a neuron, the properties is actually to be excitable. So we'll find action potential. And you have neuron to neuron connections, by the synapse. I guess that's, you know what I'm talking about. So, at this stage, we are ready to learn the integrate of all these properties of the neuron that is actually how a brain use to get the information from the outside, and then use this information to get a perception about the outside world and also internal state of your own body. And then based on this, you'll make a perception. Based on perceptions, then you need to make a action. So the action then is to control your body to adapt to the outside world. So this is really important for the sensory system. Then you scan for quite comprehensive part in the neuroscience study. So let's take a look. This is a experiment for to show, actually is a to mimic a bird. So you looking at this picture and you will see, this one can be a tail or a head. So, if this one is a tail then this should be a head. So this is the wing. So, if you pretend this kind of a target, Moving in this direction, then you will see actually this is a bird actually with a short neck. The neck is very short, but a very long tail, all right. But then you move the other side, then it's different. You have a bird with a very long neck but a very short tail. So, if you have a chicks, the young chicks, special chick. Look at this target moving about the In the sky, then the chicks will have a different behavior. For example, if the target is moving, To the right slide, and then it looks like a goose. A goose has a long neck, a short tail. And then for a chick, then it's okay, it's not dangerous at all. But then when you move to the other side, then it's dangerous, then it's a. So for a chick then, we'll respond in a very reproducible behavior. That is if you have a target, this target moving this side, the chicks will immediately escape. This escape behavior, actually, is quite robust. That means, actually, if you test, definitely individual chicks, they would have the same behavior. It doesn't matter if it's very young, very small chick, or adult chick. So that means, this behavior, kind of escaping behavior, is an innate behavior. So that means when the chicks was born, and already this behavior is controlled by the gene, already programmed the neural circuitry for this behavior. And of course if you go to this side, the target, and then the chicks actually doesn't care. So that means this guy use the sensory system, actually you see it's very important for the animal. That is, the visual system to judge whether there is a enemy or a predator like a and then you need survive. They make the actions, right, corresponding one. Okay, so from this, you already know the sensory system is critical for the survival. And let's look at another one. Of course, the sensory system is also important not only for the survival or this escaping behavior. Also maybe for the prey or for the food. This is a picture, essentially in complete darkness. [FOREIGN]. So of course this is a [FOREIGN] it's a. Of course this animal is very keen in the auditory system and also the visual system. So, when in complete darkness this guy still can catch the a small rat or mouse there, actually in the jungle. So, how this animal actually detect this target, right now you don’t have any light coming. So that means this guy uses the auditory system. Look at these pictures, then you know it's very sensitive, because maybe this small guy actually hide in the jungle. [FOREIGN]. This big animal then maybe sit somewhere a tree. [FOREIGN]. Then you need to hear very far away some small noise there. [FOREIGN]. So you need a very sensitive system to detect this information. But then very important, so sensitive is not enough you need actually a precise location, you need actually [FOREIGN].